Duplicate code is one of the most pungent code smells. A rule that is often used is to re-structure code once it is duplicated in three or more places.
Common duplication problems, and corresponding solutions are:
Complex classes like Connection often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes. You can also have a look at the cohesion graph to spot any un-connected, or weakly-connected components.
Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.
While breaking up the class, it is a good idea to analyze how other classes use Connection, and based on these observations, apply Extract Interface, too.
1 | <?php |
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16 | class Connection extends ClientConnection |
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17 | { |
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18 | |||
19 | /** |
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20 | * @var boolean |
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21 | */ |
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22 | public $use_encryption = false; |
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23 | |||
24 | /** |
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25 | * @var boolean |
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26 | */ |
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27 | public $authorized; |
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28 | |||
29 | /** |
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30 | * @var integer |
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31 | */ |
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32 | public $lastId = 0; |
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33 | |||
34 | /** |
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35 | * @var XMPPRoster |
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36 | */ |
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37 | public $roster; |
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38 | |||
39 | /** |
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40 | * @var XMLStream |
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41 | */ |
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42 | public $xml; |
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43 | |||
44 | /** |
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45 | * @var string |
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46 | */ |
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47 | public $fulljid; |
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48 | |||
49 | /** |
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50 | * @var integer|string Timer ID |
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51 | */ |
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52 | public $keepaliveTimer; |
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53 | |||
54 | /** |
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55 | * Get next ID |
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56 | * @return string |
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57 | */ |
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58 | public function getId() |
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63 | |||
64 | /** |
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65 | * Called when the connection is handshaked (at low-level), and peer is ready to recv. data |
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66 | * @return void |
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67 | */ |
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68 | public function onReady() |
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76 | |||
77 | /** |
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78 | * Called when session finishes |
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79 | * @return void |
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80 | */ |
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81 | public function onFinish() |
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93 | |||
94 | /** |
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95 | * @TODO DESCR |
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96 | * @param string $s |
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97 | */ |
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98 | public function sendXML($s) |
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103 | |||
104 | /** |
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105 | * @TODO DESCR |
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106 | */ |
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107 | public function startXMLStream() |
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113 | |||
114 | /** |
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115 | * @TODO DESCR |
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116 | * @param string $xml |
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117 | * @param callable $cb |
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118 | * @callback $cb ( ) |
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119 | * @return boolean |
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120 | */ |
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121 | View Code Duplication | public function iqSet($xml, $cb) |
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131 | |||
132 | /** |
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133 | * @TODO DESCR |
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134 | * @param string $to |
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135 | * @param string $xml |
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136 | * @param callable $cb |
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137 | * @callback $cb ( ) |
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138 | * @return boolean |
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139 | */ |
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140 | View Code Duplication | public function iqSetTo($to, $xml, $cb) |
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150 | |||
151 | /** |
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152 | * @TODO DESCR |
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153 | * @param string $xml |
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154 | * @param callable $cb |
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155 | * @callback $cb ( ) |
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156 | * @return boolean |
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157 | */ |
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158 | View Code Duplication | public function iqGet($xml, $cb) |
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168 | |||
169 | /** |
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170 | * @TODO DESCR |
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171 | * @param string $to |
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172 | * @param string $xml |
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173 | * @param callable $cb |
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174 | * @callback $cb ( ) |
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175 | * @return boolean |
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176 | */ |
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177 | View Code Duplication | public function iqGetTo($to, $xml, $cb) |
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187 | |||
188 | /** |
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189 | * @TODO DESCR |
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190 | * @param string $to |
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191 | * @param callable $cb |
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192 | * @callback $cb ( ) |
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193 | * @return boolean |
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194 | */ |
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195 | public function ping($to = null, $cb = null) |
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206 | |||
207 | /** |
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208 | * @TODO DESCR |
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209 | * @param string $ns |
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210 | * @param callable $cb |
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211 | * @callback $cb ( ) |
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212 | * @return boolean |
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213 | */ |
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214 | public function queryGet($ns, $cb) |
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218 | |||
219 | /** |
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220 | * @TODO DESCR |
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221 | * @param string $ns |
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222 | * @param string $xml |
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223 | * @param callable $cb |
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224 | * @callback $cb ( ) |
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225 | * @return boolean |
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226 | */ |
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227 | public function querySet($ns, $xml, $cb) |
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231 | |||
232 | /** |
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233 | * @TODO DESCR |
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234 | * @param string $to |
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235 | * @param string $ns |
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236 | * @param string $xml |
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237 | * @param callable $cb |
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238 | * @callback $cb ( ) |
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239 | * @return boolean |
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240 | */ |
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241 | public function querySetTo($to, $ns, $xml, $cb) |
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245 | |||
246 | /** |
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247 | * @TODO DESCR |
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248 | */ |
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249 | public function createXMLStream() |
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315 | |||
316 | /** |
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317 | * Send XMPP Message |
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318 | * @param string $to |
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319 | * @param string $body |
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320 | * @param string $type |
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321 | * @param string $subject |
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322 | */ |
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323 | public function message($to, $body, $type = 'chat', $subject = null, $payload = null) |
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345 | |||
346 | /** |
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347 | * Set Presence |
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348 | * @param string $status |
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349 | * @param string $show |
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350 | * @param string $to |
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351 | * @param string $type |
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352 | * @param integer $priority |
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353 | */ |
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354 | public function presence($status = null, $show = 'available', $to = null, $type = 'available', $priority = 0) |
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394 | |||
395 | /** |
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396 | * @TODO DESCR |
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397 | * @param string $jid |
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398 | * @param callable $cb |
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399 | * @callback $cb ( ) |
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400 | */ |
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401 | public function getVCard($jid = null, $cb) |
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428 | |||
429 | /** |
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430 | * Called when new data received |
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431 | * @return void |
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432 | */ |
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433 | public function onRead() |
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440 | } |
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441 |
This check looks from parameters that have been defined for a function or method, but which are not used in the method body.